What Canadians Are Actually Mixing With Cannabis

Cannabis use has become increasingly common across Canada since legalization, but the story does not end with cannabis itself. What people choose to use alongside cannabis can reveal just as much about consumer behavior, potential risks, and emerging trends as cannabis use alone.

For many people, cannabis is not always consumed in isolation. Sometimes it is paired with alcohol during social gatherings. In other cases, it may be used alongside prescription medications or other psychoactive substances. These combinations can influence how cannabis affects the body and may change both the potential benefits and risks associated with use.

A 2026 study published in the International Journal of Drug Policy set out to explore this issue in greater detail. Rather than simply asking whether Canadians use cannabis, researchers examined which substances are most commonly used at the same time as cannabis and whether distinct patterns of co-use exist among consumers. The results provide a fascinating look at cannabis use in a legal market and offer important insights for public health, harm reduction, and consumer education. Let’s dive in.

Why Simultaneous Substance Use Matters

Researchers use the term simultaneous use to describe situations where cannabis and another substance are used close enough together that their effects overlap. This differs from someone who might use cannabis one day and consume alcohol several days later. Simultaneous use occurs when both substances are active in the body at the same time, potentially creating interactions that alter intoxication levels, impairment, or side effects.

Understanding these patterns is important because combining substances can sometimes increase risks. For example, cannabis and alcohol together may lead to greater impairment than either substance alone. Other combinations may produce unpredictable effects that are not yet fully understood by researchers. As cannabis use continues to grow, experts increasingly believe that understanding what people combine with cannabis may be just as important as understanding cannabis use itself.

Examining Cannabis Co-Use in Canada

To better understand these behaviors, researchers analyzed data from the 2023 Canadian Substance Use Survey. The study included more than 12,000 Canadians who reported using cannabis during the previous year. Participants were asked whether they had used cannabis simultaneously with various substances, including alcohol, hallucinogens, prescription medications, stimulants, and other drugs.

Using a statistical technique known as latent class analysis, researchers searched for hidden patterns within the data. Rather than treating all cannabis consumers as one group, this method identifies clusters of people who share similar behaviors. The goal was to determine whether distinct patterns of simultaneous use exist and whether certain demographic or cannabis-related characteristics were associated with those patterns.

Three Distinct Patterns Emerged

The analysis revealed three clear groups of cannabis consumers.

The first and by far the largest group accounted for nearly 83% of participants. Individuals in this category reported relatively little simultaneous use overall. While they occasionally combined cannabis with alcohol, they generally did not report frequent simultaneous use with a wide range of other substances.

A second group was characterized by combining cannabis with both alcohol and hallucinogens. Interestingly, this pattern appeared separate from broader polysubstance use, suggesting that some consumers selectively pair cannabis with specific substances rather than combining it recklessly with multiple drugs.

The third and smallest group demonstrated a much broader pattern of simultaneous use. Individuals in this category were more likely to combine cannabis with several different substance types, including alcohol, hallucinogens, prescription medications, and stimulants.

These findings suggest that cannabis consumers are far from a uniform population. Instead, different groups appear to have different motivations, experiences, and risk profiles. The fact that nearly 83% of participants fell into the low simultaneous-use category is encouraging, as it indicates that most cannabis consumers are not routinely combining cannabis with numerous other substances. However, the smaller groups identified in the study highlight important patterns that may warrant targeted education and harm-reduction efforts.

Alcohol Remains the Most Common Mix

One of the clearest findings from the study was the prominent role alcohol continues to play in cannabis co-use. Researchers found that occasional simultaneous use of cannabis and alcohol was common across the sample. This aligns with previous research showing that alcohol is the substance most frequently combined with cannabis.

Previous research has shown that combining alcohol and cannabis can increase impairment and may lead to stronger intoxication than using either substance alone. Studies have also linked the combination to poorer reaction times and impaired decision-making.

Because this pattern appears relatively widespread, researchers suggest that public education efforts may need to devote more attention to helping consumers understand the potential risks associated with using alcohol and cannabis together.

The Rise of Cannabis and Hallucinogens

Another notable finding involved the group that combined cannabis with alcohol and hallucinogens. Previous studies have often grouped hallucinogens into broader categories of “other drugs,” making it difficult to understand their specific relationship with cannabis use. By examining hallucinogens separately, researchers identified a distinct pattern that may have gone unnoticed in earlier analyses.

The researchers speculate that this pattern may be linked to social environments such as festivals, concerts, and other recreational settings where hallucinogens are more commonly used. Some individuals may use cannabis alongside these substances to enhance certain experiences or moderate unwanted effects.

The finding is particularly interesting given growing public interest in psychedelic substances and increasing discussions about their potential therapeutic applications. As attitudes toward hallucinogens evolve, understanding how they are used alongside cannabis may become an increasingly important area of research.

Who Faces Higher Co-Use Risks?

The study also explored which factors were associated with different simultaneous-use patterns. Age, sex, income, cannabis use frequency, and reasons for cannabis use all played a role.

Younger individuals and males were more likely to fall into the group characterized by cannabis use alongside alcohol and hallucinogens. Meanwhile, lower income levels were associated with membership in the broader simultaneous-use group involving multiple substances. Researchers also found that individuals who used cannabis more frequently and those reporting more cannabis-related problems were more likely to belong to one of the higher simultaneous-use groups.

These findings suggest that simultaneous use may serve as an indicator of elevated risk and could help identify populations that may benefit from targeted education or harm-reduction resources.

Medical Cannabis Users Showed Unique Patterns

The study also examined people who reported using cannabis exclusively for medicinal purposes. Researchers found that medicinal-only cannabis users were more likely to belong to the group characterized by broad simultaneous use involving prescription medications and other substances. However, it is important to note that this does not necessarily mean these individuals are misusing medications, as the prescription drugs are most likely part of legitimate treatment plans for their health conditions. However, this does highlight an important area for future research, as scientists still have much to learn about how those combinations influence treatment outcomes, symptom management, and safety.

What This Means for Harm Reduction

The study reinforces the idea that cannabis education should move beyond simple discussions of use versus non-use. Instead, harm-reduction efforts may benefit from focusing on the specific combinations consumers are using and the contexts in which those combinations occur.

For example, educational campaigns could provide clearer information about the effects of mixing cannabis with alcohol. Healthcare providers may also benefit from discussing cannabis use alongside prescription medications, particularly among patients who use cannabis for medical purposes.

The researchers also noted that policymakers could consider creating educational campaigns focused specifically on simultaneous use behaviors.

Looking Ahead

As cannabis becomes a more established part of Canada’s legal landscape, understanding how it fits into broader patterns of substance use will become increasingly important. This study reveals that most Canadian cannabis users are not regularly combining cannabis with other substances. At the same time, it highlights several distinct groups whose patterns of simultaneous use may carry different levels of risk.

The findings offer an important reminder that cannabis consumption does not occur in a vacuum. What people use alongside cannabis may significantly influence their experiences, potential harms, and health outcomes. For researchers, healthcare providers, and policymakers alike, the future of cannabis harm reduction may depend not only on understanding cannabis itself, but also on understanding the company it keeps.

References:

^{1. Kyra N. Farrelly, Jeffrey D. Wardell, Simultaneous use of cannabis with other drugs: Identifying latent classes in a sample of Canadians, International Journal of Drug Policy, Volume 155, 2026, 105379, ISSN 0955-3959, https://doi.org/10.1016/j.drugpo.2026.105379}